Wireless communication systems use electromagnetic waves to communicate with wireless communication devices located within cells of coverage areas of the systems. A radio spectral range or band designated or allocated for a wireless communication service or a particular class of wireless services may be divided into different radio carrier frequencies for generating different communication frequency channels. This use of different frequencies for different communication channels may be used in various multiple access radio wireless communication systems.
Wireless communication systems provide a hand-over or hand-off (HO) process where a mobile station (MS) changes from communications with one base station (BS) to communications with another adjacent base station due to motion of the mobile station or other reasons. For example, the hand over may be initiated when the MS moves in its location due to signal fading, interference levels, etc. at the current serving base station and thus needs to change another base station to which the MS is connected in order to provide a higher signal quality. In another example, a hand over may be initiated when the MS can be serviced with higher quality of service (QoS) at another base station. Such a hand over process can be used to ensure continuing communication services to the MS and may be implemented in different ways. For example, a hand over process can be configured to operate the MS to simultaneously communicate with and to receive and send communication traffic with two or more adjacently located base stations and to synchronize the data among the different communication traffic flows with the different base stations during the hand over process.
In various wireless communication systems such as a Mobile Network system, Data Integrity Schemes have been defined and used to prevent packet data loss during normal packet transmission, handover or other situations within the system.